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Derivative Instruments and Hedging Activities Interest Rate Sensitive Assets/Liabilities (Details) (USD $)
In Thousands, unless otherwise specified |
Dec. 31, 2014
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Dec. 31, 2013
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| Derivatives, Fair Value [Line Items] | ||
| Available-for-sale securities | $ 14,341,102us-gaap_AvailableForSaleSecurities | $ 12,256,727us-gaap_AvailableForSaleSecurities |
| Interest-Only-Strip [Member] | ||
| Derivatives, Fair Value [Line Items] | ||
| Available-for-sale securities |
$ 55,686us-gaap_AvailableForSaleSecurities / us-gaap_DebtSecurityAxis = us-gaap_InterestOnlyStripMember |
$ 75,575us-gaap_AvailableForSaleSecurities / us-gaap_DebtSecurityAxis = us-gaap_InterestOnlyStripMember |
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- Definition
Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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